Exploring the World Ocean embodies the belief that oceanography is best taught as an Earth systems science; one that acknowledges the connections and interactions between the atmosphere, Earth, and ocean. It was written explicitly to inform and educate students about the world ocean and the ongoing efforts of 21st century oceanographers to understand it. It can be used in a traditional, content-rich, format or applied to active and inquiry-based exploration of fundamental questions and current topics. Exploring the World Ocean generally follows the order of topics presented in traditional oceanography textbooks, however; many topics have been reduced, merged, and expanded to offer contextual as well pedagogical improvements over existing texts. Rather than devote separate chapters to oceanographic history and environmental issues, these topics are embedded within each chapter. By featuring a brief history of the science at the start of each chapter, students can trace the historical development of a particular field of study and better see science as a progression of ideas and discoveries that builds on previous work. In a similar light, environmental issues are addressed within the context of the topic being discussed so that students can witness the application of particular field of study to a specific human problem.