The hydrosphere consists of all the water on, over, and under Earth's surface. More than 70 percent of Earth's surface is covered by liquid water. Water can also be found frozen in ice caps and glaciers, and in the air as water vapor and clouds. Discover more in Hydrosphere, a title in the Earth's Systems series. This series provides readers with an in-depth look at the atmosphere, biosphere, hydrosphere, and lithosphere, examining how these four "spheres" work individually and together to form the dynamic system that is Earth. Lightbox is an all-inclusive digital solution for the teaching and learning of curriculum topics in an original, groundbreaking way. Lightbox is based on National Curriculum Standards. Lightbox assesses the Seaming of vocabulary and key concepts with printable activities and graded, emailable quizzes. Lightbox digital titles come packed with fully integrated media features, including embedded videos, slideshows, child-safe weblinks, and the entire body of the text read aloud. Unique features of Lightbox enable students to virtually visit locations with Google Maps. Book jacket.